ASoC: rsrc-card: add convert channels support

Renesas sound device has CTU (= Channel Transfer Unit), and
sound card needs its support.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/renesas,rsrc-card.txt

@@ -30,6 +30,7 @@ Optional subnode properties:
 - frame-inversion			: bool property. Add this if the
 					  dai-link uses frame clock inversion.
 - convert-rate				: platform specified sampling rate convert
+- convert-channels			: platform specified channel size convert
 - audio-prefix				: see audio-routing
 - audio-routing				: A list of the connections between audio components.
 					  Each entry is a pair of strings, the first being the connection's sink,

sound/soc/sh/rcar/rsrc-card.c

@@ -66,6 +66,7 @@ struct rsrc_card_priv {
 	struct snd_soc_dai_link *dai_link;
 	int dai_num;
 	u32 convert_rate;
+	u32 convert_channels;
 };
 
 #define rsrc_priv_to_dev(priv) ((priv)->snd_card.dev)
@@ -144,11 +145,16 @@ static int rsrc_card_be_hw_params_fixup(struct snd_soc_pcm_runtime *rtd,
 	struct rsrc_card_priv *priv = snd_soc_card_get_drvdata(rtd->card);
 	struct snd_interval *rate = hw_param_interval(params,
 						      SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval *channels = hw_param_interval(params,
+						SNDRV_PCM_HW_PARAM_CHANNELS);
 
-	if (!priv->convert_rate)
-		return 0;
+	if (priv->convert_rate)
+		rate->min =
+		rate->max = priv->convert_rate;
 
-	rate->min = rate->max = priv->convert_rate;
+	if (priv->convert_channels)
+		channels->min =
+		channels->max = priv->convert_channels;
 
 	return 0;
 }
@@ -436,9 +442,13 @@ static int rsrc_card_parse_of(struct device_node *node,
 	/* sampling rate convert */
 	of_property_read_u32(node, "convert-rate", &priv->convert_rate);
 
-	dev_dbg(dev, "New rsrc-audio-card: %s (%d)\n",
-		priv->snd_card.name ? priv->snd_card.name : "",
-		priv->convert_rate);
+	/* channels transfer */
+	of_property_read_u32(node, "convert-channels", &priv->convert_channels);
+
+	dev_dbg(dev, "New rsrc-audio-card: %s\n",
+		priv->snd_card.name ? priv->snd_card.name : "");
+	dev_dbg(dev, "SRC : convert_rate     %d\n", priv->convert_rate);
+	dev_dbg(dev, "CTU : convert_channels %d\n", priv->convert_channels);
 
 	ret = rsrc_card_dai_link_of(node, priv);
 	if (ret < 0)